Electric riveting-machine



P. M. BENEDICT.

ELECTRIC RIVETING MACHINE.

APPLICATION FILED MAR. 6. 1916.

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rammed July 13,' 1920.

3 SHEETS-SHEET I.

P. M. BENEDICT.

ELECTRIC RIVETING MACHINE.

APPLICATION FILED MAR. 6, 1916.

V U77, D

W/ TNESSES C Y/N VENT( uc.

- 'ha uw' E P. M. BENIEDICT.

ELECTRIC RIVETING MACHINE.

APPLICATION FILED MAR. 6, I9I6.

-@SHEETS-SHEET 3.

Patented. July 13, 1920.

UNITED STATES PATENT, OFFICE. A

PAUL 2M. BENEDICT, 0F NEW HAVEN, CONNECTICUT, ASSIGNOR TO THE BARNES &

-KCBEET MANUFACTURING 4Coiviriin'r,vor iviiLLnALE, CONNECTICUT, A CORPORA-v TION OIE CONNECTICUT.

Y ELECTRIC EIVETINGLMACHINE.

To all whom t may concer/n.'

Be it known that LPAUL M. BENEDLCT, a citizen of the United States, residing in the city and county of New Haven and State of Connecticut, have invented certain new and useful Improvements in Electric Riveting-Machines, of which the following is a full, clear, and eXact description.

rlhis invention relates to a machine,` ap paratus or press for electric riveting, welding and similar operations, and more particularly -to a machine of the type which is adapted to oin two parts by riveting, heading or clenching a rivet shank or the like, that is heated by means of lan electric current. My improved machine is of special utility in `the manufacture ofy insulator brackets, strain insulatorsl and various `articles of hardware, but it may be used to advantage in the manufacture of inany widely diierent articles.

One of the primary objects of the present invention is the provision of a machine or press in which the electric current is so supplied to the work piece yand traverses the same `in such a way that it is effectively heated prior to the riveting or other bending or working thereof It is also aimed to furnish a `machine kwhich will operate indefinitely without necessitating repairs and which is very quick `and convenient in operation, while atthe same time it is economical in the consumption of current.

'Another object of the invention is torturnish an improved electric riveting machine or pressin which the work is heated while held stationary between suitabledie members, by bringing an electrode in contact with Ysaid work piece, said electrode being mounted on a carrier which also supports a working plunger or punch,and said carrier y being conveniently movable `so that when the electrode is moved out of ,y Contact with the work piece the aforesaid Vplunger may be quickly and conveniently moved into aline- `mentv with the work piece and caused to descend on the same so` as to form the hot `.neta-l into a rivet head, or perform such` other operationV as may be necessary.

VThe invention also has in view the general improvement inthe construction and operation of machines orapparatus of tliertype to which the invention relates.

y specification of Letters Patent. Patented July 13, 1920 Application ined March c, 1916. sei-iai No. 82,495. i

To 'these and other ends, the invention consists in the novel features and combination of parts to be hereinafter described and claimed.

', rivetingpress or machine embodying my Y improvements; n

Y Fig, 2 is a front elevation of the same;

Fig. 3 isan enlarged fragmentary perspective view of the movable electrode, the metal bending plunger, the dies for holding the work piece, and the'watcr connections for cooling the electrode and they dies;

Fig. 4 is a fragmentary section on line lLl---l of Fig. 2;

Fig. 5 -is a fragmentary section on line 5,5 of Fig. 2; y

F ig'. 6 is a rear 'elevation of tlic upper por tion of the machine with the belt pulley omitted;

F ig.V 7 isa detail plan view of the dies and the lower conductor plates;

Fig. 8 isa front elevation,"partly in section', of the parts shown in Fig.'7;

Fig. 9 is a horizontal detail section through the movable electrode holder;

Fig. l() is a side elevation, partly tion, of said electrode holder;

Fig. 10a is a `'sectional view of one of the plates yconnected with a die member;

Figs. 11, 12 yand 13 are diagrams showing diiferent stages of the operation of the .inachine; and i y Fig. le is a diagrammatic view of a mount ing for a work holder.

Referring to the drawings, l have illustrated my improvements as applied to a machine in the nature of a press having a die bed, Va vertically reciprocating plunger, and an upper power shaft from which the plungenis operated. The frame A of the press in secis of more or less usual construction, being provided with a suitable base 20, from which L n n u l rise side frames or standards 2l that Join each other at the top of the machine where hearings 22, 23 are provided fora driving shaft 24 driven in the ordinary manner by i a belt pulley 25, or other suitable means. At

the upper front part of the nfiacliine,` the frame carries a guide or slideway 26 in front of the bearing 2?) in whichrslideway a crosshead 27 is adapted to reciprocate vertically.

This cross-head 27 is engaged by a crank pin on the forward end of the shalt 2li, so that as the shaft is rotated, the cross-head or slide 27 is moved up and down. As usual in machines el this character, a clutch B of suitable construction is interposed between the driving pulley 25 and the driving sha :t This clutch is normally disengaged, but by actuating a treadle C, the shalt 2d may be rotated to cause the descent oli tie slide or cross-head, which will 'then operate the riveting` punch or plunger, as hereinafter described.

lh-e punch or plunger actuated by the slide 2T is not rigidly connected with said s1 le, but is mounted on a carrier inovably supported on tl a machine 'traine so as to be moi/*able over the worlt piece. 1n the partienV ar liorin snown, the carrier which supports the pl'lniger is in the form of a swinging bearing plate or block 29 mounted Vto turn about a vertical airis. lJrelcrably, the plate or bloclt 29 is swiveled in the machine between the side trames by means of an upright stud shaft 30. The plate or bloei: has a hub embracing` said shaft, The lower e1. l of the shaft is supported in a step bearing in a cross-web 32 of the machine iframe, and said shaft is provided with another bearing at the top ot the frame, as indicated at 33 in Fig. l. Extending rearwardly vfrom the bearing bloelr or carrier 2S) is an arm 34:, located at the rear oli the shaft ifi-O, as shown at Fig. 4l.

fit the liront of the carrier or block 20, 'the same is provided with a separable beai'ng 'for a vertically arranged plunger This plunger is adapted to reciprocate vertically, and rotary movement thereof in the bearing is prevented by the polygonal cross section oli Jthe plunger, which eiigages a correspond lj; s raped opening` in the carrier or bloeit. ,Y c ending upwardly beyond the bearing bloeit is a neel: portion 3G at the upper part o'lA` 'the plunger surinounted by head 37. llie heed 3'? is 'n'elierably in the shape oi a dish, and it engages a slot in the lower end l rl`his slot 8S is ot T-rhailied of the slide .f\c':..c,.\ #-fvs n. l i l i tl A U- :[3'11 J-l 'L cross cellen Uune open at ne oo coin .in tno passage oli the neck 536. Alter the head or dif-sli 2&7 has been inserted into the slot irom one rnd, the plun ""r will be connected lide 27 mr vertical movement in :l i the s both directions with said slide, as will be obvious, irrespective oli the lengthwise movement oli the head il? in 'the slot Ell. ln plan, the slot 3P) is oli arcuate form, the center et the curve being coinei dent with the center or the swivel stud or shalt 530, so that the plunger, in spite of its connection with the slide Q7, may be moved laterally of 'the machine in either direction by movement olf the carrier 29.

ln the particular form shown, a si'iitable electrodo holder is mounted on the carrier at one side of the riveting plunger and adapted to move vertically. In this particug lar instance, the electrode holder is mounted at the lower end oli a vertically sliding spin dle mounted at the leiit ol the riveting plunger, as shown in Fig. 2. rlhe slide or spindle tlis' mounted. in upper and lower bearings lO on the carrier member 29 which project later Jlly from that portion which guides the riveting plunger, and th spindle supports at its lower end beneath 'the lower bearing an electrode or electrode holder, as hereinafter more particularly described. F or the purpose el" raising and lowering the spindle 39, a suitable operatino lever ll may be provided, which lever is pivoted inten mediate of its ends to the carrier QS), at 1.12, in such a manner as to swing in a vertical plane, the forward portion ot said lei'er eri:- tending through a slot lil in the spindle 3f) and being pivoted to the spindle in said slot by a pin 44. At the liront extremily, the lever l1 is provided with a suitable operai' in@ handle Preferably, the electrode-ein'- rying spindle is normally held in a raised position by appropriate means, such as a counliierweight 4G on the rear end of the lever Aell. ln this way, the electrode is normally hel d at some distance above the worlq, as hereinafter described, although it may be depressed at any time by pulling down on 'the operating lever Ll-l as will be understood. Y

The work holding devices are pre'leral'ily mounted beneath the plunger or punch and the electrode holder in the l'ollowing mauner: At the lower front part of the press, a table l) is mounted so to be vertically adjustable. In the particular 'form shown, the table D is mounted in a slideway in the front of the machine frame, and is adapted to be raised and lowered by rotating a 'leed screw a7. On top oit the table is a member or fixture 48 in the nature of a guide, which is adjustable both longitudinally and transversely ot' the machine frame. The length* wise adjustment or the lixture 4S may; be effected by means such as screws 4l!) passing through. a bracket 50 secured to one end or' the table and abutting one end oil the guide member /l-S, and. a screw e'lfl" soeleteifl in the table and engagin'Y a shoulder a8 on the fixture or member at the end opposite the screws Traumreise :nljustment oll the member 48 may be eileeted by movn ing it in place by approiaiate meansv such cam-headed bolts l-ll when the adjustment has been effected. 1Vertical adiustment can, of course, be obtained bv liiliting or lowering the table l). The member d8 serres as a mountingt'or a work holder composed of a pair oli' relatively movable work holding elements or jaws 50, 5l. laeh of these work holding jaws comprises a supporting block and a die plate or meinber surmounting the same, there being a suitable conducting plate for conveying the electric current, interposed between the block and the die plate, as hereinafter described. The jaw 50 in the present instance is intended to be stationary, whereas the jaw 51 may be moved toward and away from the same in a direction lengthwise of the diehead. VBoth of the jaws are preferably mounted in an undercut groove in the member 48, and in the particular form shown, the jaw 5l has alateral extension 52 on its supjfiorting block connected by a link 53 with a crank disk 54 mounted to turn on a lateral extension of the member 48. The link 53 is pivoted eccentrically oi' the disk, and the latter may be turned by an operating lever 55, for the purpose of'moving the holder jaw 5l in the desired direction in its guideway. In the position shown in Fig. 4, the jaw 5l is moved into close proximity to the jaw 50, butv by turning the operating lever 55'in the direction of the arrow,.the jaw 51 may be shifted to the right to separate the jaws, :as shown in Fig. 5.

Each of the jaws 50, 5l isV provided with a die Vplate 56 clamped to the top of the same, andthe work piece is intended to be tightly clamped in the die formed by the shoulder. The steel die plates are provided with recesses 57 at their meeting edges, adapted to accommodate a portion of the shank including the shoulder. In other words, the die plates in conjunction form a cylindrical die or seat which tightly lits the shank when the jaws 50, 5l are brought together, as shown in Fig'. l2, the upper portion of the cylindrical seat being cut away to receive the shoulder on the j bracket shank. @wing to the curved Vjorm oi the work piece selected for illustration, the supporting block of the jaw or member 5i is cut away so that the jaws will clamp only the upper portion of the shank. In the particular form shown, each of the die plates 56 is secured on its supporting block by a clamping screw 58 located centrally or" the die plate, and for the sake of economy each die plate, which is of square shape, is provided at each side with a recess or half socket 57 adapted yto coperate with aA similar half-socket of the Aother die in seating the work piece. Thus, when one of the work receiving sockets formed conjointly in the two diev platesis worn or otherwise injured, the plates can be turned on their axes soras to4 provide an entirely new die socket.

The work piece is heated `electrically by passing a currentthrough the portion thereof which is to be riveted or upset, suoli current traversing both of the die plates 56 and an electrode 59, which is carried by the spindle-39, and is moved down into contact with the upper end of the bracket shank or other work piece. In the particular form shown, the upper movable electrode 59 adapted to make contact with the upper end of the work piece is moimted in a separate electrode holder 60, as best shown in Figs. 3, 9 and 10. This electrode holder is connected by conductors 61 -with one pole of the secondary coil of a suitable transformer 62, supplied with current 'from an appropriate source, while the other pole of such secondary coil or winding 'is connected by suitable conductors G3 with the die plates 56 by way of appropriate conducting plates 64 interposed between the die plates and their respective supporting blocks. In this manner, when the work piece is clamped in place between the die plates, the electrical circuit will be completed by contact of the' electrode 59 with the upper end of the work piece, as

shown in Fig. 12, and with a transformer and conductors of proper capacity and design the protruding end of the work piece which is to be headed or riveted can be quickly heated to the required temperature for eiiicient riveting.

In the particular example illustrated, the electrode holder is insulated from its carrier and from other'parts of the machine structure, the current being grounded in the machine through the conducting plates 6i. rFhe electrode holder 6U is preferably composed of a massiveblock of copper, which is the best material known for this purpose, and the copper block ris provided with a 'Flange 6l;L by means of which it is clamped by bolts 62a to a flange 63a on the. lower end of the supporting spindle 39, the insulation of the electrode block from the rest of the machine being provided for by interposingsuitable insulating material in the flanged joint, as shown at 64 in Fig. l0. The electrode proper 59 is in the form ot a rod suitably socketed in the lower end portion of the holder block, and in order to maintain the electrodeat a sufficiently low temperature duringtheloperation of the machine, suitable means should be provided for cooling the same. In the particular form shown,

a water passage 65 in the lower end of the holder extends around the electrode 59. Water is conducted to the passage 65 by a flexible tube 66. It is also necessary to cool the die plates' tol prevent them from becoming red-hot during the operation or" the Cil machine, and in the particular example illustrated, the water circulating through the passage in the electrode holder passes out 'troni such electrode holder through a ilexible tube (37, thence into a water passage G8 in one et the d'e plates thence through a flexible tube to a similar passage 68 in 'the other die plate, and thence to waste 'through a tube 7l). The water passage, s in the die plates may be formed by drilling holes parallel to the respective sic es, and then plugging up 'the ends oi' certain holes with small screw plugs, as shown in llig. '7, and the water passages in the electrode holder may be drilled in a similar' manner.

ln a machine of this kind, the heating current is very large, say eight thousand amperes, but there is an extremely low potential, say one and one-halt volts. It is obvious, therefore, that in the machine itself the current must at all points be conducted with a minimum oit resistance, and in making connect-ions in the electric` circuit, it has been found necessary to provide tight joints or connections of lr e cross-sectionlin the 'form shown, conne tion of the scc4 ondary winding ol the transformer with the electrode holder is made by four conductors Gl oit large cross-section, which enter sockets 7l ol? a connecting plug 72, ei'igaging a socket 755, in the intermediate rait of the electrode holder. rl`his plug 72 is prei? erably made ol'" copper and is tapered toward the forward end, the socket 73 being correspondingly tapered and being extended through the electrode 'roin front to rear. fr bridge piece 74 extends across the socket at the 'front so as to be supported at its ends on the side portions oi the electrode holder, and a bolt or screw l 5 passes through tnis bridge piece into engagement with a threaded socket 76 in the forward end or. the tapered plug. lt will be understood, 'there llore, that by screwing the bolt Z5 into the socket of the plug, the plug will be drawn ilorward in the tapered soi-liet .'l. ln tl way, by `lnjoviding clean, smooth contactin,ly surfaces between the plug` and the socket in the electrode holder, and drawing thel plug as 'lar `Forward as possible by means ol'A the bolt, the plug and electrode holder nuty he held in tight contact over a surface ol considerable area, so that the current will hare no appreciable resistance o'llered to its p ssa lit will be coservcd lr in llig. 'that portions ol the electrode holder which are cisposed at opposite sides of the plug are oli considerable cross-sectional arca.

Referring now to the conducting plat s (34, it will be observed that each of these plates is oli considerable area so as to make Contact with the under surface of the corresponding die plate over a considerable area. The upper surface of each plate is clean and smooth, and the lower surface of' the corresponding die plate is clean and smooth, so that when the corresponding screw 5S vis tightened, the two plates will make good electrical contact with cach other. he plates 6l are preferably made of copper 4ol: considerable thickness, and preferably they are connected with the conducting wires in substantially the same manner in which the conducting wires are connected with the electric holder. For this purpose, each or' the conducting plates is provided at its rear extremity with a downturned flange 77 having a tapered socket 78 similar to the socket 73 in the electrode holder. A tapered plug (9 of copper similar to the plug 72, having sockets 80 in which two conductors (33 are soldered, engages the socket 78 and is tightly clamped therein by means of a bolt 8l and bridge piece 82 in substantially the manner previously described.

It has been previously stated that the clutch B is operated by the treadle C when it desired to actuate the cross-head 2'? and the plunger' 35. ln actuating the press to depress the plunger, it is necessary to pull down a rod 83 'forming a part of an ordinary clutch mechanism. In order, however, to prevent depression of the plunger' except when it is in line with the work piece, the rearwardly extending arm of the carrier is provided with a perforation Sil adapted to be moved into and out or' registry with a pin 85 which moves downward when the rod 83 is pulled down. In the -forni shown, the rod 88 is connected to one end or' a lever 8G pivoted to the trame at 87, and connected intermediate oi its ends with the pin S5, as shown in Fig. 6. lVhen the riveting plunger is in line with the work piece, as shown in Fig. 13, the hole or perforation il' rmed in the outer end of the extension 34 is in line with the pin S5 so that the latter can pass through it to permit the pulling down of the rod 83 and the actuation ot the clutch, but when the riveting plunger is out of line with the work piece, the solid. portion olf the arm or extension Bil of the carrier, blocks the downuuird movement ol the pin 85 and thereby prevents the actuation ot the clutch tor causing the descent olz the plunger.

The operation ol the improved machine will be more or less obvious lrom the iloregoing description. It will be apparent that the carrier E29 can be readily swung to the right or lett by means of the operating lever al, which is also used to depress the electrode. Adjustable stops 88 ol' a suitable kind are carried by the side frames of the machine so as to limit the swing olt the carrier in both directions. In Fig. 2, the electrode is in a position to descend vertically on the workpiece.` In Fig. 11, the electrode is somewhat to the left of the work piece, but by actuating the lever 11it may be brought into line with the same. The work is clamped between the die plates 56 by operating the lever 55, as previously described, whereupon the electrode is moved down into contact with the upper end of the work piece, as shown in Fig. 12. Thus, the

alternating electric current which is prefer to a high temperature, while the electrode is momentarily held in contact with the Work piece by depression Yof the operating lever. The lever is then vreleased sol that its counterweight will raise it again, and during the raising movement lateral pressure is exerted on the lever so as to vswing lthe carrier into a vposition in which the plunger 35 is in line with the work piece. The treadle C is then depressed` and as the driving shaft 211V is then actuated to operate the cross-head 27, the plunger is forcibly brought down .on the heated shank of the Work piece so as to rivet or clench it, or perform some other operation depending upon the character ofthe work.

While I have described with considerable particularity the embodiment of my invention selected for illustration I wish tol have it understood that various changes in the details of the construction may be made without departing from my inventive idea as expressed in the claims.

What I claim is 1. In a machine such as described, Vthe combination of separate die plates adapted to clamp the work between them, conductor plates in contact with the respective die plates, electric conductors connected with lsaid conductor plates, and a movable eleccombination of a pair of supporting nieml bersmovable relatively to each other, conductor plates 'of extended area arranged flatwise in contact with the respective members, die` plates mounted on the respective conductor plates and adapted to clamp the work, electric conductors connected with said conductor plates, and an electrode having a different electric conductor connected thereto and adapted to contact with the work while the latter is held by said die plates, said die plates having passages through which cooling Awater is Conducted; substantially as described. Y

4:. Ina machine such as described, the combination of a slideway, a pair of supporting blocks mounted therein, conductor plates superposed. on the respective blocks, die plates superposed on said conductor plates and adapted to clamp the work between them, an electricv conductor connected with the respective conductor plates, and an electrode having a different electric conducter connected 'thereto and adapted to f `5. In a machine such as described, the

combination of afdie plate, a copper conductor plat-cof considerable area lying flatwise against the die plate, `detachable means for interelanfiping said plates, the conductor plate being extended laterally beyond the die plate, a flexible electric conductor, and detachable means for connecting said leXible conductor with the laterally extending portion of theconductor plate so as to inv sure a good electrical connection between said parts.

6. In a machine such as described, thecombination of a die plate, a conductor plate of extended area beneath the die plate, detachable means for clamping the die plate tightly against the upper surface of the conductor plate, a flexible electric conductor, a tapered plug permanently connected with one end of said flexible conductor, and engaging a tapered socket in said conductor plate, and adjustable means for forcing said i plug into said socket so as to obtain a good electrical connection between the said parts.

7. In ,a machine such as described, the combination of a slideway, a pair of supporting blocks mounted therein, conductor plates superposed on the respective blocks, die plates superposed on said conductor plates and'adapted to clampthe work be# tween them, said conductor plates being` provided with tapered sockets, a' tapered plug adjustably mounted in each oi said sockets, means for moving said plugs into tight Contact with the walls of the sockets, an electric conductor connected with the respective plugs, and an electrode having a dilerent electric conductor connected thereto and adapted to close the circuit by contacting with the work piece.

8. ln a machine such as described, the con'ibination of a slideway, a pair of supporting blocks mounted therein, conductor plates superposed on the respective blocks, die plates superposed on said conductor plates and adapted to clamp the work between them, said conductor plates being provided with tapered sockets, a tapered plug adjustably mounted in each of said sockets and means comprising a bridge piece extending across the socket, a coperating member for moving said plugs into tight contact with the wall of the sockets, an electric conductor connected with the respective plugs, and an electrode connected with a dii'lerent electric conductor and adapted to close the circuit by contacting with the work piece.

9. ln a machine such as described, the combination ol' a work-supporting die adapted to support a work piece therein, an electrode movable into contact with said work piece, electrical conductors adapted t0 supply current to said die and electrode, and means for connecting said conductors to said die and to said electrode, including tapered sockets having tapered plugs tightly mounted therein.

l0. In a machine such as described, the combination oi' a work-supporting die adapted to support a work piece therein, an electrode movable into Acontact with said work piece, electrical conductors adapted to supply current to said die and electrode, and means secured to said die and said electrode for electrically connecting the conductors thereto, each of said means having a tapered socket formed therein, a tapered plug adjustably mounted in each of said sockets, a bridge piece extending across cach of said sockets having cooperating means for moving said plugs into tight engagement with the walls of the sockets and means `for securing said conductors to said plugs; substantially as described.

1l. In a machine such as described, a pair of relatively movable supporting blocks, die plates mounted upon said blocks and adapted to clamp the work between them, a conductor plate positioned between at least one of said blocks and its die, said conductor plate being provided with a tapered socket, a tapered plug adjustably mounted in said socket, means fonmoving said plug into tight contact with the walls oit the socket, an electric conductor connected with said plug, and an electrode having a diill'erent electric conductor connected thereto and adapted to close the circuit by contacting with the work piece.

In witness whereof I have hereunto set my hand on the 4th day oit March, 1916.

PAUL M. BENEDICT.

(Sii 

